In Euclidean plane geometry, a quadrilateral is a polygon with four edges and four vertices. A quadrilateral is a trapezoid or a trapezium if 2 of its sides parallel to each other. A quadrilateral is a parallelogram if two pairs of sides parallel to each other. Squares and Rectangles are special types of parallelograms. With four interior angles present, the sum of the interior angles of a quadrilateral is 360 degrees
,/br> Quadrilaterals are classified based on their intersecting nature. If they are not intersecting, they are called simple quadrilaterals. Otherwise, if they happen to self-intersect, it is a complex quadrilateral. Simple quadrilaterals are further classified into concave and convex quadrilaterals based on the position of diagonals and their interior angles. The Chapter has problems solved using the essential topics like Quadrilateral and some terms associated to it, Angle sum property, Types of quadrilaterals, Properties of a parallelogram, Properties of a rectangle, rhombus and a square and useful facts about the triangle.